The construction of many gas burning apparatuses require that the gas-air mixture escaping from the burners is very lean. A lean mixture is defined as a low percent of gas with respect to air. Often the percentage of gas can be so low that the mixture comes close to the lower limit of flamability. The closer the mixture is to the limit of flamability the higher the required spark energy for ignition will be. The required spark energy can become prohibitive to the application of any ignition control on the market.
A gas apparatus of this construction might have a direct spark ignition control of the type manufactured and sold by Honeywell Inc. as the S87D Direct Spark Ignition Control Module wherein, upon energization of the burner, a spark electrode provides a spark to ignite the gas and once the flame is present a flame detection system turns off the ignition system. In order to enhance the ignition, raw or pure gas has been admitted in the vicinity of the electrode to enrich the gas-air mixture which reduces the required ignition energy.
Recognizing the need for enriching the gas in the vicinity of the ignition system spark to reduce the required spark energy, the present invention is concerned with an improvement in the ignition apparatus. A unit made up of a conductive tube or pipe attached adjacent to a high voltage electrode by an insulating member provides the spark portion of the ignition system. With such a unit, the unit can be easily installed on a gas heater such as a radiant gas burner, with a minimum effort, ensuring that the spacing of the electrode from the grounded tube and the admittance of raw gas to the area are adequate to provide ignition from a particular ignition system.